A walking-beam conveyor for the stepped conveyance of metal coils or sheet-metal bundles, sheet packs, or similar conveyed stock typically has at least one walking beam that is raised and lowered by lifters between lateral support rails and is movable by at least one longitudinally effective actuator in the longitudinal transport direction. The sheet-metal or wound-up metal strips are also designated as coils.
Preferably, such a walking-beam conveyor has a plurality of walking beams arranged successively in the workpiece-travel direction that are moved step-wise downstream and upstream jointly. At the same time, the walking beams are jointly raised while moving downstream and lowered while moving back such that the coils or the like resting on the lateral support rails can be conveyed in steps in the workpiece-travel direction. A walking-beam conveyor of this type can be integrated as conveying equipment, for example, in rolling mills. However, they are appropriate for use in all types of rolling plants and processing lines, such as, for example, pickling lines, surface-coating equipment, shearing lines, conveyance systems connecting various equipment, etc. These walking-beam conveyors are characterized by high strength and flexibility. The simple design of the delivery points allows for angled branching from the conveyor line, reversibility, as well as independent feeding and discharging of the coils. Additional advantages of walking-beam conveyors are the modular design and floor-level conveying surface. As a result, these walking-beam conveyors are suitable, for example, for conveying coils, for example, hot coils at the output point of hot-rolling mills. They can be employed both at the intake section (feed for the coils) as well as at the output (removal area for the coils), and are suitable for the conveyance of hot and cold coils.
An example of a walking-beam conveyor of the type described in the introduction was disclosed in U.S. Pat. No. 4,387,800. The longitudinally effective actuator is designed as a cylinder that steps the walking beam downstream and upstream. This patent also describes a walking-beam conveyor in which the travel or beam drive is designed as a toothed rack drive comprising a hydromotor and a drive pinion that engages a toothed rack disposed on the underside of the walking beam.
Walking-beam conveyors of this type are proven technology. In practice, however, it has been found that the transport or conveyance path is limited since the overall load of a plurality of walking beams disposed in succession is very high. This aspect is combined with a relatively expensive construction. For this reason, chain conveyors are in practice frequently employed, in particular for long conveying distances. These chain conveyors are utilized primarily for long conveyor lines and, for example, for hot-coil cooling lines. However, a robust design comparable with walking-beam conveyors cannot be easily achieved with such chain conveyors. This is the starting point for the invention.